Preimplantation genetic diagnosis (PGD) is performed to screen for inherited diseases. In PGD, one or two cells are removed from the developing embryo and tested for a specific genetic disease. Embryos that do not have the gene associated with the disease are selected for transfer to the uterus. These procedures require specialized equipment and experience and IVF in a couple who may not need IVF to conceive.
The benefit of screening the embryos for disease in couples at risk and reducing the risk of having an affected child or terminating a pregnancy is preferable to some couples. While PGD can reduce the likelihood of conceiving a pregnancy with an affected child, it cannot eliminate the risk. Confirmation with chorionic villus sampling (CVS), amniocentesis or other testing is still necessary.
